diff --git a/src/component/mypage/Mypage.tsx b/src/component/mypage/Mypage.tsx
index d3002b5a..7a1fcb8f 100644
--- a/src/component/mypage/Mypage.tsx
+++ b/src/component/mypage/Mypage.tsx
@@ -4,6 +4,7 @@ import { myPageTabList } from "../../constant/tablist";
 import { useTabFocus } from "../../hook/useTabFocus";
 import { useNewDialog } from "../../hook/useNewDialog";
 import { useGetUsersSearchId } from "../../api/users/useGetUsersSearchId";
+import { lendingRestriction } from "../../util/date";
 import MyRent from "./MyRentInfo/MyRent";
 import MyReservation from "./MyReservation";
 import MyReview from "./MyReview";
@@ -65,35 +66,6 @@ const Mypage = () => {
     };
   }, []);
 
-  const concatDate = (day: Date) => {
-    if (!userInfo) return "";
-    let overDueDate = "";
-    day.setDate(day.getDate() + userInfo.overDueDay);
-    overDueDate += day.getFullYear();
-    overDueDate += "-";
-    overDueDate +=
-      day.getMonth() + 1 >= 10
-        ? day.getMonth() + 1
-        : "0".concat(`${day.getMonth() + 1}}`);
-    overDueDate += "-";
-    overDueDate +=
-      day.getDate() >= 10 ? day.getDate() : "0".concat(`${day.getDate()}`);
-    return overDueDate;
-  };
-
-  const getOverDueDate = () => {
-    if (
-      !userInfo ||
-      (userInfo &&
-        (!userInfo.penaltyEndDate ||
-          new Date(userInfo.penaltyEndDate).setHours(0, 0, 0, 0) <
-            new Date().setHours(0, 0, 0, 0)))
-    ) {
-      return concatDate(new Date());
-    }
-    return concatDate(new Date(userInfo.penaltyEndDate));
-  };
-
   return (
     <>
       {deviceMode === "desktop" && (
@@ -170,11 +142,8 @@ const Mypage = () => {
                   </span>
                   <span className="font-14-bold color-54">대출제한</span>
                   <span className="font-14">
-                    {userInfo.overDueDay ||
-                    (userInfo.penaltyEndDate &&
-                      new Date(userInfo.penaltyEndDate).setHours(0, 0, 0, 0) >=
-                        new Date().setHours(0, 0, 0, 0))
-                      ? `${getOverDueDate()} 까지`
+                    {lendingRestriction(userInfo).isRestricted
+                      ? `${lendingRestriction(userInfo).restrictionDate} 까지`
                       : "-"}
                   </span>
                   <span className="font-14-bold color-54">정보수정</span>
diff --git a/src/component/userManagement/UserBriefInfo.tsx b/src/component/userManagement/UserBriefInfo.tsx
index 7205cb1b..50664cc7 100644
--- a/src/component/userManagement/UserBriefInfo.tsx
+++ b/src/component/userManagement/UserBriefInfo.tsx
@@ -1,8 +1,9 @@
+import { User } from "../../type";
+import { lendingRestriction } from "../../util/date";
 import Image from "../utils/Image";
 import UserUsage from "../../asset/img/book-arrow-right.svg";
 import UserEdit from "../../asset/img/edit.svg";
 import "../../asset/css/UserBriefInfo.css";
-import { User } from "../../type";
 
 const roles = ["미인증", "일반", "사서", "운영진"];
 const USAGE = 1;
@@ -26,30 +27,7 @@ const UserBriefInfo = ({ user, line, setModal, setSelectedUser }: Props) => {
     setModal(EDIT);
   };
 
-  const concatDate = (day: Date) => {
-    let overDueDate = "";
-
-    day.setDate(day.getDate() + user.overDueDay);
-    overDueDate += day.getFullYear();
-    overDueDate += "-";
-    overDueDate += day.getMonth() + 1 < 10 ? "0" : "";
-    overDueDate += day.getMonth() + 1;
-    overDueDate += "-";
-    overDueDate += day.getDate() < 10 ? "0" : "";
-    overDueDate += day.getDate();
-    return overDueDate;
-  };
-
-  const getOverDueDate = () => {
-    if (
-      !user.penaltyEndDate ||
-      new Date(user.penaltyEndDate).setHours(0, 0, 0, 0) <
-        new Date().setHours(0, 0, 0, 0)
-    ) {
-      return concatDate(nowDay);
-    }
-    return concatDate(new Date(user.penaltyEndDate));
-  };
+  const { isRestricted, restrictionDate } = lendingRestriction(user);
 
   return (
     <div className={`user-info ${line ? "user-info-line" : ""}`}>
@@ -68,12 +46,7 @@ const UserBriefInfo = ({ user, line, setModal, setSelectedUser }: Props) => {
       )}
       <div className="user-info__email font-18-bold color-54">{user.email}</div>
       <div className="user-info__overdue font-18 color-54">
-        {user.overDueDay ||
-        (user.penaltyEndDate &&
-          new Date(user.penaltyEndDate).setHours(0, 0, 0, 0) >=
-            new Date().setHours(0, 0, 0, 0))
-          ? getOverDueDate()
-          : "-"}
+        {isRestricted ? restrictionDate : "-"}
       </div>
       {user.nickname ? (
         <button
diff --git a/src/util/date.ts b/src/util/date.ts
index 42267704..ae9ea114 100644
--- a/src/util/date.ts
+++ b/src/util/date.ts
@@ -1,11 +1,10 @@
-import { isNumber, isString } from "./typeCheck";
-/*  기본적인 날짜표시 형식 20yy-mm-dd */
+import { User } from "../type";
 
+/*  기본적인 날짜표시 형식 20yy-mm-dd */
 const dateReg = /^(20\d{2})-(0?[1-9]|1[012])-(0?[1-9]|[12][0-9]|3[01])$/;
 
 export const isFormattedDate = (string: string) => RegExp(dateReg).test(string);
 export const dateFormat = (string: string) => {
-  if (isFormattedDate(string)) return string;
   return string?.slice(0, 10)?.replace(".", "-") || "";
 };
 
@@ -22,9 +21,16 @@ export const splitDate = (string: string) =>
     ?.map(v => parseInt(v)) || [];
 
 /* string 형식의 날짜 비교 */
+export const compareDate = (
+  date1: string,
+  date2 = nowDate,
+  compare: (date1: string, date2: string) => boolean,
+) => {
+  return compare(dateFormat(date1), dateFormat(date2));
+};
+
 export const dateLessThan = (date: string, now = nowDate) => {
-  if (!isString(date) || !isString(now)) return undefined;
-  return dateFormat(date) < now;
+  return compareDate(date, now, (date1, date2) => date1 < date2);
 };
 
 /* 날짜 및 시간 계산 */
@@ -44,10 +50,27 @@ export const isExpiredDate = (expireDateString: string) => {
 };
 
 export const addDay = (num: number, date = nowDate) => {
-  if (!isString(date) || !isNumber(num)) return date;
-  const splited = splitDate(dateFormat(date));
-  if (!splited) return date;
-  const [year, month, day] = splited;
-  const dateObj = new Date(year, month - 1, day);
+  if (!isFormattedDate(date)) return date;
+  const dateObj = new Date(date);
   return dateFormat(addDayDateObject(dateObj, num).toISOString());
 };
+
+/* lending 관련 날짜 함수 */
+
+export const lendingRestriction = (user: User) => {
+  // 대출제한날짜는 이미 반납한 대출건의 연체제한 + 대출중인 도서의 연체일로 계산
+  const restrictionDate =
+    !user.penaltyEndDate || dateLessThan(user.penaltyEndDate)
+      ? addDay(user.overDueDay) // 오늘 날짜 + 대출중인 도서를 오늘 반납시 받게 될 연체일
+      : addDay(user.overDueDay, user.penaltyEndDate);
+  // 이미 반납한 대출건의 연체 제한날짜 + 대출중인 도서를 오늘 반납시 받게 될 연체일
+
+  // 대출제한날짜가 현재 날짜보다 크면 대출제한
+  const isRestricted = compareDate(
+    restrictionDate,
+    nowDate,
+    (d1, d2) => d1 > d2,
+  );
+
+  return { isRestricted, restrictionDate };
+};